Azo dye.



UNITED STATES Patented May 2, 1905.

PATENT OFFICE.

PAUL JULIUS AND ERNST FUSSENEGGER, OF LUDWIGSHAFEN-ON-THE- RHINE,GERMANY, ASSIGNORS TO BADISOHE AN ILIN & SODA FABRIK, OFLUDWIGSHAFEN-ON-THE-RHINE, GERMANY, A CORPORATION OF BADEN.

AZO DYE.

SPECIFICATION forming part of Letters Patent N0. 789,096, dated May 2,1905.

Application filed February 18, 1905. Serial No. 246,307-

To a, whom it may concern.-

Be it known that we, PAUL JULIUS and ERNST FUSSENEGGER, doctors ofphilosophy and chemists, subjects of the Emperor of Austria-Hungary,residing at Ludwigshafen-onthe-Rhine, in the Kingdom of Bavaria, Ger--man Empire, have invented new and useful Improvements in AzoColoring-Matter Suitable for Use in the Form of its Lakes,of which thefollowing is a specification.

Our invention relates to the production of an azo coloring-matter which,in the form of its lakes, possesses excellent properties, being verystable against the action of light. A

Although the azo coloring-matters prepared from a mono-substitutedanilin and beta-naphthol disulfo-acid R in the form of their lakes are,as a rule, worthless, we have discovered that the azo coloring-matterprepared by combining diazotized para-chlor-anilin with betanaphtholdisulfo-acid R possesses,in the form of its lakes, very beautiful shadesand great coloring power and is also very stable against the action oflight.

The following example will serve to further illustrate the nature of ourinvention, which, however, is not confined to this example. The partsare by weight.

Diazotize in the usual manner one hundred and twenty-seven and a half(127 .5) parts of para-chlor-anilin and allow the clear diazo solutionto run into a stirred solution of three hundred and fifty (350) parts ofthe sodium salt of 2-naphthol-3.6-disulfo-acid, to which also suflicientsodium carbonate has been added to maintain the whole alkaline. Stir forhalf an hour (thirty minutes) and then heat to a temperature of fromfifty to sixty degrees Centigrade, (50 to 60 C.) Complete theprecipitation of the coloring-matter by means of common salt, filteroff, and press and dry.

The coloring-matter consists of a brownred powder which is easilysoluble in hot water. Its barium salt possesses a deep bluered color andis almost insoluble in water. Upon reduction with tin and hydrochloricacid it yields para-chlor-anilin and amidonaphthol disulfo-aoid.

Now what we claim is.

As a new article of manufacture the azo coloring-matter which can beobtained by combining diazotized para-chlor-anilin with 2- naphthol-S.ti-disulfo-acid, which coloring-matter consists of a brown-red powdereasily soluble in hot water, and which in the form of its barium salt isalmost insoluble in water, and which upon reduction with tin andhydrochloric acid yields para-chlor-anilin and amido-naphtholdisulfo-acid.

In testimony whereof we have hereunto set our hands in the presence oftwo subscribing witnesses.

PAUL JULIUS. ERNST FUSSENEGGER. Witnesses:

ERNEST F. EHRHARDT, Jos. H. LEUTE.

